The present invention relates to a multi-piece solid golf ball composed of a core, an envelope layer, an intermediate layer and an outer layer that have been formed as successive layers. More specifically, the invention relates to a multi-piece solid golf ball in which importance is placed on achieving an excellent flight when the ball played by ordinary amateur golfers who do not have a very high head speed, and on having a good, soft feel on impact.
Key performance features required in a golf ball include distance, controllability, durability and feel on impact. Balls endowed with these qualities in the highest degree are constantly being sought. Among recent golf balls, there has emerged a succession of balls which have multilayer structures and are typically composed of three pieces. By making the structure of a golf ball multilayered, it is possible to combine numerous materials of differing properties, thus enabling a wide variety of ball designs in which each layer has a particular function.
Also, golf balls in which importance is placed on distance and a soft feel are widely used as balls for ordinary amateur golfers. Therefore, a major challenge is to design the thickness and hardness of the respective layers of the ball in such a way as to maximize these effects. Yet, there are limitations in the design of hardnesses and thicknesses in two-piece solid golf balls and three-pieces solid golf balls. Numerous disclosures, such as those indicated below, have been made on multilayer balls having four pieces or five pieces.
Golf balls with such a multilayer structure have been disclosed in, for example, JP-A 2009-160407, U.S. Pat. No. 6,302,808, JP-A 2001-017569, JP-A 2001-017570, JP-A 2001-037914, JP-A 2000-61002, JP-A 2000-60997, JP-A 2000-61000, JP-A 2000-61001, JP-A 2001-218872, JP-A 2005-218859, JP-A 8-336618 and JP-A 9-56848.
However, in such prior-art golf balls with a multilayer structure, because importance is often placed on numerous qualities other than flight, such as spin rate on approach shots, feel on impact and durability, they lack a sufficient spin rate-lowering effect on full shots, leaving room for further improvement in the distance traveled on shots with a driver.